MicroRNAs (miRNAs) are small non-coding RNA molecules, on average 22 nucleotides long, that function in transcriptional and post-transcriptional regulation of gene expression. Encoded by eukaryotic nuclear DNA, miRNAs function via base-pairing with complementary sequences within mRNA molecules, usually resulting in gene silencing via translational repression or target degradation. The human genome may encode over 1000 miRNAs, which may target about 60% of mammalian genes and are abundant in many human cell types. Aberrant expression of miRNAs has been implicated in numerous disease states, and miRNA-based therapies are under investigation.
For example, Zhu et al. (Cardiovascular Research, 2011, 92:75-84) found that microRNA-195 (miR-195) promotes palmitate-induced apoptosis in cardiomyocytes by down-regulating Sirt1.
Wang et al. (PLoS ONE, 2012, 7(6):e38885) found that serum miRNA signatures can predict mortality in sepsis patients.
There remains a need to identify one or a combination of miRNAs that can be specifically targeted to treat or prevent various disease states.